:185-206. Skwaryło-Bednarz B. Zawartośćtłuszczu oraz tokoferoli w nasionach krajowych odmian szarłatu ( Amaranthus cruentus L.) w warunkach zróżnicowanego nawożenia makroelementami. Acta Agrophys. 2010;15(2):407-415 (in Polish). Ratusz K, Wirkowska M. Charakterystyka nasion i lipidów amarantusa. Oilseed Crops. 2006;XXVII(2):243-250 (in Polish). Gajewska R, Lebiedzińska A, Malinowska E, Szefer P. Ocena jakości zdrowotnej szarłatu (amarantusa). Roczn PZH. 2002;53(2):141-147 (in Polish). Bressani R, Gonzales JM, Elias LG, Melgar M. Effect of fertilizer application on the yield
Supercooling Points of Apis Mellifera Ligustica when Performing Different Age-Related Tasks
In order to study the cold resistance of honey bees, the authors systematically investigated the supercooling points (SCPs) of Apis mellifera ligustica worker bees performing different age-related tasks. There were statistically significant differences in SCPs between worker bees performing different activities (P<0.05). The nectar-water collector had the highest SCP temperature (-3.16°C), highest water content (74.85%) and lowest crude fat content (6.13%). The soldier had the lowest SCP temperature (-6.40°C), relatively lower water content (70.33%) and higher crude fat content (7.28%). No significant difference was found in the SCPs of workers of different ages. Winter bees did not differ from summer bees in their SCPs. The relatively higher SCPs from different kinds of individual bees suggest that honey bees do not mainly rely on their low SCPs for their cold resistance.
Effect of Pasture or Maize Silage Feeding on the Nutritional Value of Beef
The objective of this study was to evaluate the nutritional value of beef from different production systems. The study was conducted with Hereford bulls on organic and conventional farms. On the organic farm, fattening was mainly based on roughages, including pasture forage in the summer season, when the end of fattening occurred. On the conventional farm the bulls were fed maize silage and concentrate. On both farms, the animals were aged 7-9 months at the beginning of fattening. The bulls were fattened to a final body weight of 550-600 kg. Samples of longissimus thoracis muscle were collected from half-carcasses of slaughtered bulls originating from each farm to analyse fat content, fatty acid profile, and content of selected minerals and vitamin E. Muscle samples were additionally analysed for the concentration of thiobarbituric acid-reactive substances 3 and 7 days after slaughter. Analyses showed a lower fat content in longissimus thoracis muscle of bulls from the pasture feeding system. The fatty acid profile was also characterized by a lower content of C 14:0, and a higher content of polyunsaturated fatty acids (PUFA), including C18:3 n-3, conjugated linoleic acid, C 20:5 n-3, and C 22:5 n-3, as well as by a lower ratio of n-6/n-3 PUFA. The total content of monounsaturated fatty acids was significantly higher in animals fed maize silage and feed concentrate. In turn, the muscle of pasture fed animals had higher levels of Na, Zn and Fe as well as of vitamin E.
Analysis of Relationships Between Fattening and Slaughter Performance of Pigs and the Level of Intramuscular Fat (IMF) in Longissimus Dorsi Muscle
The aim of the study was to determine the level of basic fattening and slaughter traits (growth rate, level of meatiness and fatness, age at slaughter) depending on different levels of intramuscular fat that determine different sensory perceptions of consumers. Subjects were 4430 gilts from pedigree farms, which were tested in performance stations. The breed composition of the animals was as follows (head): Polish Large White - 1240, Polish Landrace - 2083, Puławska - 104, Hampshire - 35, Duroc - 152, Pietrain - 208, line 990 - 608. Animals were kept in individual pens and fed standard diets. Intramuscular fat (IMF) content of the longissimus dorsi muscle was determined by Soxhlet using the SOXTHERM SOX 406 system (Gerhardt). The level of IMF served as a basis for dividing the test animals into three groups: below 2% (group I), between 2% and 3% (group II) and above 3% (group III). Animal breed had the highest and highly significant effect on the level of all traits analysed. As regards age at slaughter and carcass meat percentage, an interaction was found between animal breed and the group factor determined based on IMF level (P≤0.001). The factor expressed as IMF group had no effect on the level of analysed traits (P>0.05). Therefore, the results of this analysis concerning the parameters obtained from live evaluation do not permit these data to be used in selection for improved IMF levels. The high rate of lean deposition in the modern breeds prevented genetic differences in the level of IMF to fully manifest themselves at a slaughter weight of about 100 kg. This unfavourable information leads one to look for other factors that determine variation of this trait.
Nutritional Value and Technological Suitability of Milk from Cows of Three Polish Breeds Included in the Genetic Resources Conservation Programme
The study included milk obtained from cows of three native cattle breeds, i.e. White-backed (BG), Polish Red (RP) and Polish Black-and-White (ZB) kept under conventional conditions. The reference group consisted of milk from Polish Holstein-Friesian cows (PHF) maintained in the intensive system and milk from Simmental cows (SM) kept under conventional conditions. The following parameters were determined in 976 samples of milk: content of fat, protein, casein, lactose and solids; acidity (pH value); heat stability; rennet coagulation time; content of α-lactalbumin, β-lactoglobulin, serum albumin, lactoferrin and lysozyme. Additionally, a certain proportion of samples was investigated for fatty acid profile and content of macro- and microelements. Cows of native breeds produced milk of higher nutritional value (higher content of whey proteins and polyunsaturated fatty acids, including CLA) and more suitable for processing as compared to PHF cows. Milk from cows of the Polish Red breed was the most valuable in terms of these parameters, which can be associated with a distinctive phylogenetic origin of this breed. The favourable parameters in regard to the nutritional value and technological suitability of milk obtained from analysed population of cows of 3 breeds included in the programme of genetic resources conservation are therefore an important reason of validity for subsequent implementation of this programme.
Normal development of piglets is determined principally by the milking ability of the sows. This study attempted to determine the relationships between sow’s milk quality and rearing performance of the piglets. The experiment was carried out under uniform conditions, with standard feeding of the sows and a similar number of piglets per litter. The study accounted for 109 lactations of second- and third-parity Polish Large White (PLW ) sows and 123 lactations of second- and third-parity Polish Landrace (PL) sows. Colostrum and milk were collected from the sows at 1, 7, 14 and 21 days of lactation and analysed for solids, crude protein, fat, lactose and somatic cell count (SCC). Rearing performance of second- and third-litter piglets was determined based on the number and weight of piglets at birth and at 7, 14 and 21 days of age. The coefficients of correlation, estimated between basic composition of milk and rearing performance of the piglets over subsequent weeks of lactation were low and exceeded r = 0.200 only for some traits. The experiment showed that a higher content of basic milk components, in particular protein, may be one of the factors contributing to an increase in weight gain of piglets during a 21-day lactation. Milk fat content may be of significance for rearing performance of piglets only during their first week of life. Rearing performance of the piglets is unrelated to udder health expressed as milk SCC.
Functional foods, defined as “foods that may provide health benefits beyond basic nutrition”, became increasingly popular in the past twenty years with numerous practical applications. In Europe, functional foods must be accompanied by scientifically substantiated health claims. Products which aspire to that category include poultry meat and processed meat products which have been modified through bird nutrition. This article reviews the existing knowledge about foods fortified with health-promoting additives. It discusses the physiological, economic and legal aspects of modifying poultry meat, including turkey meat which has been poorly investigated in this context. The addition of oils rich in PUFA (polyunsaturated fatty acids), e.g. linseed oil, to poultry diets has been found to increase LC n-3 PUFA (long-chain omega-3 PUFA) concentrations in chicken and turkey meat. LC n-3 PUFAs participate in many processes that condition metabolism and health, and the nutritional value of meat, including poultry, is most commonly enhanced by increasing the proportion of LC n-3 PUFAs in the product's fatty acid composition. However, it increases feed costs and may cause a deterioration in the sensory attributes and oxidative stability of meat. Turkey breast meat is characterized by a relatively low fat content, which is why the fulfilment of health claim requirements is difficult in the European Union.
Fat and cholesterol content and fatty acid profiles in edible tissues of spiny-cheek crayfish, Orconectes limosus (Raf.) from Lake Gopło (Poland)
The aim of the present work was to determine the fatty acid profiles, total cholesterol content, and the fat percentage in the meat of the abdominal section of spiny-cheek crayfish, Orconectes limosus (Raf.), caught in Lake Gopło. A total of 177 males (aged 3+ and 4+) were collected in spring and summer for the analyses. The meat of crayfish caught during spring had higher fat contents (1.09 % in 3+ individuals and 1.10 % in older crayfish) than that in individuals from summer at 0.92 and 1.05%, respectively. Differences among these means were not statistically significant (P > 0.05). The total cholesterol content was higher in the meat of crayfish caught in summer (71.98 mg 100 g-1), and these values differed significantly from those obtained from individuals in spring (65.32 mg 100 g-1). In all groups of crayfish analyzed, the main SFA was C16:0, MUFAs were dominated by C18:1 n-6, and the highest percentage of PUFAs was of C20:5 n-3.
The Composition of Fatty Acids in Muscles of Six Freshwater Fish Species from the Mazurian Great Lakes (Northeastern Poland)
Lipid content and fatty acids composition of non-predatory fish: roach, Rutilus rutilus (L.), bream, Abramis brama (L.), vendace, Coregonus albula (L.), and of predatory fish: Eurasian perch, Perca fluviatilis L., pike, Esox lucius L. and burbot, Lota lota (L.) were examined. These fish were caught from three lakes of Mazurian Great Lakes (Kisajno, Dargin, Niegocin). The content of total lipid and some fatty acids varied widely within and among species. Generally, the lipid content was low (0.56-2.78%). Among the saturated and monounsaturated fatty acids, the predominant fatty acids were palmitic C16:0 (19.24-33.44%), stearic C18:0 (4.37-6.87%), palmitoleic C16:1 (4.51-12.93%), and oleic C18:1 n-9 (6.85-14.49%). Arachidonic C20:4 n-6 (3.17-6.55%), eicosapentaenoic C20:5 n-3 (4.14-8.91%), and docosahexaenoic C22:6 n-3 (5.91-24.67%) acids were the most abundant polyunsaturated fatty acids. In the case of all the freshwater fish, with the exception of bream, higher contents of saturated fatty acids than monounsaturated fatty acids were noted. Among the fish studied, the highest value of total n-3 polyunsaturated fatty acids (43.86%) was noted in vendace, whereas bream contained the highest content of total n-6 polyunsaturated fatty acids (11.21%). The ratio of n-3/n-6 ranged between 1.50 (burbot) and 4.40 (vendace). Differences in the content of fatty acids in fish with different feeding strategies (non-predatory and predatory) were measured. Non-predatory fish were found to have lower values of saturated fatty acids than predatory fish (P ≤ 0.05). Non-predatory fish contained significantly more eicosapentaenoic acid (EPA) than predatory fish (P ≤ 0.01), whereas the amounts of monounsaturated and n-3 and n-6 polyunsaturated fatty acids in non-predatory and predatory fish were not statistically significant (P > 0.05). The total n-3 polyunsaturated fatty acids was higher in non-predatory fish, but not statistically significant (P > 0.05). Similarly, the differences in DHA and n-3/n-6 ratio in muscles of predatory and non-predatory fish were not statistically significant (P > 0.05).
An experiment was conducted on 600 broiler chickens to determine the effect of using Camelina sativa oil as a dietary component on meat quality indicators. Broiler chickens were raised on litter under standard conditions of feeding and maintenance. In the second period of rearing, the control group (I) received a diet containing 6% rapeseed oil. Experimental groups were fed on a diet containing 3% rapeseed oil and 3% Camelina sativa oil (group II) and 6% camelina oil (group III). At the end of rearing 8 chickens from each group were slaughtered. A simplified analysis of the carcasses was conducted. Blood samples were taken to determine the content of total fat, triglycerides, total cholesterol and its fractions. Muscle samples were analysed for the content of dry matter, total protein and crude fat, fatty acid composition and malonic aldehyde (TBA). The meat was subjected to sensory evaluation. It was found that the introduction of Camelina sativa oil to the grower diet for broiler chickens does not have a negative effect on rearing parameters and carcass quality. What was observed was a tendency to reduce the proportion of abdominal fat in the carcass with increasing level of oil used in compound feed and increases in the total protein content of breast meat in group II receiving 3% of camelina oil. The addition of 6% of Camelina sativa oil to compound feed significantly decreased the content of total cholesterol and its fractions in the blood plasma of chickens in comparison to the other groups. The introduction of 3% and 6% of Camelina sativa oil to chicken diets enriched the breast meat in n-3 PUFA, mainly α-linolenic acid (ALA) and did not impair the flavour qualities of the cooked meat. The meat from chickens fed on a diet containing 6% of camelina oil was characterized by a greater increase of ALA.